Research published in the July issue of the Journal of Politics by James H. Fowler and Christopher T. Dawes of the University of California, San Diego and Laura A. Baker of the University of Southern California shows that, “individuals with a variant of the MAOA gene are significantly more likely to have voted in the 2000 presidential election.”

In an additional study published in the May 2008 issue of American Political Science Review, Fowler and Dawes used twins to identify genetic similarities and differences between adults with voting records. The twin study found that, “identical twins, who share 100 per cent of their genes, are significantly more similar in their voting behavior than fraternal twins who share only 50 per cent of their genes on average.”

“Using twins is a common approach in genetic studies since identical twins share the exact same DNA, while fraternal twins do not. At the same time, both kinds of twins are usually raised in similar family and social circumstances, giving researchers a way to tease out how much of a particular behavior might be genetically driven,” a WebMD article explains.

A new study published in the Journal of Politics ties a specific variant of the MAOA gene to voting behavior. An earlier study by two of the same researchers in the American Political Science Review found that “among identical twins … 72 per cent of the variance in voter turnout can be attributed to genes. Moreover, genetic-based differences extend to a broad class of acts of political participation, including donating to a campaign, contacting a government official, running for office, and attending a political rally,” Science Daily reports.

According to lead researcher James Fowler, “The genes have nothing to do with voters’ choices at the polling place. Instead, they may play a role on people’s desire to participate in social behavior like collective decision-making and distribution of resources.”

John T. Jost, a professor of psychology at New York University is not surprised by the results: “Unless one believes that basic psychological characteristics have no genetic antecedents whatsoever, one would have anticipated these results on the basis of the psychological literature. Still, it’s quite important that these researchers appear to have identified specific gene combinations that are linked to political orientation."

The U.S. Census Bureau provides detailed voting statistics and registration numbers. Compare voter registration to voter turnout among all recorded U.S. demographics in elections from 1964 through 2006.